Performance of computer-based analysis using temporal subtraction to assess joint space narrowing progression in rheumatoid patients

Abstract

Our computer-based method can detect the chronological change in joint space width between baseline and follow-up images as the joint space difference index (JSDI). The aim of this study was to verify the sensitivity and specificity of our computer-based method in assessment of joint space narrowing progression in rheumatoid patients. Twenty-seven patients (24 women and 3 men) with rheumatoid arthritis underwent radiography of the bilateral hand at baseline and at 1 year. The joint space narrowing (JSN) of a total of 252 metacarpophalangeal (MCP) joints and 229 carpal joints was assessed by our computer-based method, setting the Sharp/van der Heijde method as the gold standard. We constructed a receiver operating characteristic curve by using the Sharp/van der Heijde method as the gold standard and set the optimal cutoff on JSDI for MCP, carpal, and MCP/carpal joints. We then calculated the sensitivity and specificity for each cutoff in assessment of JSN progression. At the most discriminant cutoff, the sensitivity and specificity of the computer-based method for MCP joints was 78.6 versus 85.3 %, respectively (AUC = 0.837; P < 0.001). Carpal joints revealed a lower sensitivity and specificity with 64.7 and 86.8 % (AUC = 0.775; P < 0.001). Furthermore, the sensitivity and specificity for MCP/carpal joints was 71.0 versus 83.6 %, respectively (AUC = 0.778; P < 0.001). The computer-based method presented a reliable assessment of JSN progression with high sensitivity and specificity and may be useful in follow-up assessment of the joint damage in rheumatoid patients.

A reliability study using computer-based analysis of finger joint space narrowing in rheumatoid arthritis patients

“…They confirmed that when the SHS score increased between baseline and follow-up images, the JSDI tended to demonstrate higher values [11]. However, this computer-based method has not been fully validated in terms of reliability; it includes subjective manual aspects such as ROI setting and image superimposing.…”

“…We have developed a computer-based method for the assessment of joint space width difference which can objectively detect slight JSN between two images and compute the joint space difference index (JSDI) using a temporal subtraction technique [10,11]. This method allows the objective and quantitative assessment of JSN progression in patients with RA with high sensitivity and specificity [10,11], using a conventional scoring method as the standard of reference.…”

“…This method allows the objective and quantitative assessment of JSN progression in patients with RA with high sensitivity and specificity [10,11], using a conventional scoring method as the standard of reference. However, the repeatability or intra-/inter-observer reliability of this method has not been fully examined previously.…”

Radiographic quantifications of joint space narrowing progression by computer-based approach using temporal subtraction in rheumatoid wrist

“…16 A portion of our patient population has been previously reported. 15 The study was conducted in accordance with the Declaration of Helsinki and was approved by the local ethics committee. Informed consent was obtained from all patients.…”

“…Although a previous study 15 showed the relatively high sensitivity and specificity of the computer-based method for JSN progression in carpal joints as well as finger joints, it is unclear whether our computer-based method can quantify the JSN progression as well as the Sharp/van der Heijde (SvdH) method in carpal joints. Our aim in this study was to investigate the validity of our computer-based method in rheumatoid wrists.…”